This type of objective lens driving apparatus (i.e. actuator) is provided with a focus driving mechanism for driving an objective lens in a focusing direction of an optical disc, in order to focus a light spot on a track of the optical disc. In addition, in order to make the light spot follow the track of the optical disc, it is provided with a tracking driving mechanism for driving the objective lens in a tracking direction of the optical disc. At this time, along with the focus displacement or tracking displacement, the objective lens possibly gets an inclination. Moreover, synchronizing a rolling frequency with a rotation frequency of the optical disc (e.g. 160 kHz) or the like may cause a “pitching resonance” in the focusing direction or “yawing resonance” in the tracking direction. Such an inclination or resonance possibly reduces the reproduction quality or recording quality of the optical disc.
In order to handle such a failure, there has been suggested a technology of supporting a movable portion and a fixed portion, which constitutes the objective lens driving apparatus, with two pairs of suspension springs, each pair having two suspension springs, for opening the movable portion and the fixed portion in a  (or inversed V) letter shape, i.e. for making them in so-called a  (or inversed V) letter shaped structure (e.g. refer to a patent document 1). If such a  (or inversed V) letter shaped structure is adopted, rotational stiffness improves, and the inclination of the objective lens reduces. In addition, by providing symmetric driving circuits on the both edges and providing the objective lens in substantially the center of a lens holder device, the response frequency characteristic of the objective lens driving apparatus is also improved, and the resonance can be controlled.
Alternatively, if the  (or inversed V) letter shaped structure is not adopted, for example, in the objective lens driving apparatus in a Slim system in which the suspension springs are disposed in parallel, there has been suggested a technology of using a leakage magnetic flux to cancel a rotational moment around the rotation center of a high-order resonance mode, to thereby control the resonance (e.g. refer to a patent document 2).    Patent document 1: Japanese Patent Application Laid Open No. 2001-126280    Patent document 2: Japanese Patent Application Laid Open NO. Hei 11-86307